Improvement in pianos



10.113,073.` Patented Mar. 28, 1871. "Fig-l.

AQ@ v QW l/ ma mams P21525 co, PHOTQUYHO., WASHINGTON. n. c.

Aframe7 showing the binding-wires z z, theI sounding- FREDERICK MATH'USHEK, 0F NEW YORK, N. Y.

Letters Patent No. 113,073, dated March 28, 1'871.

IMPROVEMENT IN PLANOS.

The4 `Bobadilla referred to in these Letten Patent and mann; part of the luis.

To all whom it may concern:

Beit known that I, FREDERICK MATHUsHnK, of New York, in the county of New York and State of New York, have invented a new and valuable Improvement in Piano-Fortes; and I do hereby declare that the following is a full, clear, and exact description of the construction and operation of the same, reference being had to the annexed drawing making a part of this specification, and to the letters and' figures of reference marked'thereon.

Figure 1 of thedrawing is a bottom view of the board being removed.

Figure 2 is a transverse vertical section.

Figure 3 is a vertical longitudinal section.'

My invention has relation to an improvement in piano-forte fra-mes; and

It consists dn binding the longitudinal bars of the frame together by transverse strings of brass extending .across the bottom of the frame, on the opposite side of the sounding-board from the scale.

'lhe object 'of this construction is to obviate the warping effect ofthe tension of the scale on the upper side of the frame, and at the same time to provide a means for obviating, in a great degree, the tendency of the instrument to get out of tune.

The letter A of the drawing designates the metallic frame, which may be of any'form or style, horizontal, upright, or inclined.

B designates the scale side of the frame, and

C, the reverse side.

The strings of the scale are secured in the usual manner by means of the wrist-,pins and hitch-pins to the side B of the frame.

D represents the hitch-pin plate.

E designates the wrist-plank.

F represents the sounding-board.

G G are transverse braces, which are abutted on one side against the wrist-plank block H, and on the other against the bar K, which, in turn, is-abutted against the iianch L ofthe hitch-pin plate.

N represents the ilanch of the wrist-plank', which is 4turned down on the inner side of the wrist-plank block.

The braces u bi serve to keep apart the longitudinal bars of the frame, and they are placed on the oppositeside of the soundinglboard from the scale.

.The bar K is beveled on its under side downward and inward.

The wrist-plank block His provided on the inner edge of its underside with the bridge P.

a a designate the strings of the scale, and

z z', the brass binding-strings or wires, secured to the tightening-pins b in the wrist-plauk-block and to the hitch-pins c on the ilanch L of the hitch-pin plate.

These wires are of double length. They pass around the hitch-pins and are secured at each end to the tightcoing-pins b b, bywhich they are brought into proper tension.

They are designed to extend transversely across the frame in the shortest lines, and are parallel with each other, all passing over the bridge P. p

From this construction itis apparent that thetendency of the tensile force of the wires of the scale to draw or warp up the face B, is connterbalanced by the binding force of the brass wires z z on the opposite side of the frame. v'

The wires zz are made of brass, in order that they 4may have a compensatingeii'ect during changes of temperature, the object being to prevent a change of tension at such times in the strings of the scale, which are thereby designed to be kepti'n tune.

Having thus'fully described my invention,-

VVhat .I claim as new, and desire to secure by LetF ters Patent, is-` The brass compensating-wires z z, strained across the under side of lthe piano-frame, substantially as specified.

In testimony that I claim the abovel have hereunto subscribed my name in the presence of two wit DBSSGS.

FR. MATHUSHEK.

Witnesses:

FRANK B. Genus, J ons M. 

